State Paranoia Research Articles

A paradigm for the study of paranoia in the general population: The Prisoner's Dilemma Game

A growing body of research shows that paranoia is common in the general population. We report three studies that examined the Prisoner's Dilemma Game (PDG) as a paradigm for evaluation of non-clinical paranoia. The PDG captures three key qualities that are at the heart of paranoia—it is interpersonal, it concerns threat, and it concerns the perception of others' intentions towards the self. Study 1 (n=175) found that state paranoia was positively associated with selection of the competitive PDG choice. Study 2 (n=111) found that this association was significant only when participants believed they were playing the PDG against another person, and not when playing against a computer. This finding underscores the interpersonal nature of paranoia and the concomitant necessity of studying paranoia in interpersonal context. In Study 3 (n=152), we assessed both trait and state paranoia, and differentiated between distrust- and greed-based competition. Both trait and state paranoia were positively associated with distrust-based competition (but not with greed-based competition). Crucially, we found that the association between trait paranoia and distrust-based competition was fully mediated by state paranoia. The PDG is a promising paradigm for the study of non-clinical paranoia.

Being Deluded After Being Excluded? How Emotion Regulation Deficits in Paranoia-Prone Individuals Affect State Paranoia During Experimentally Induced Social Stress

Emotion regulation (ER) has become a relevant construct to understanding paranoia. While the ER strategy called expressive suppression (e.g., poker face) may foster state paranoia by increasing arousal, another strategy called reappraisal (e.g., changing the perspective on situations) may reduce negative emotions and state paranoia when adaptively used. However, if reappraisal fails, this could increase paranoia. The aim of this study was to test the proposed effects of the ER strategies on state paranoia in the socially stressful situation of being excluded in paranoia-prone individuals. We conducted an experimental online study with N=116 participants who were randomized to a social inclusion or an exclusion condition using a virtual Cyberball ball-tossing game. They completed questionnaires on paranoia proneness and habitual ER strategies. Before and after the Cyberball task, participants rated their level of state paranoia. The impact of habitual ER strategies, paranoia proneness, and social stress on changes in state paranoia was investigated using linear regression analysis. The three-way interaction of social stress, paranoia proneness, and habitual reappraisal use significantly predicted state paranoia, t(114)=2.62, p=0.010. The decomposition of the interaction term revealed that in the social stress condition, the impact of reappraisal on state paranoia was moderated by the level paranoia proneness. Specifically, in high paranoia-prone individuals the use of reappraisal predicted higher state paranoia. The findings regarding habitual use of suppression were not significant. Although reappraisal is generally considered a functional strategy, its use in distressing social situations seems to be impaired in persons with higher paranoia proneness. A working model of emotion dysregulation in delusions is presented and possible implications for cognitive therapy of psychosis are discussed.

Using signal detection theory to test the impact of negative emotion on sub-clinical paranoia

A novel experimental paradigm for measuring state paranoia by means of signal detection theory was evaluated. A liberal response bias, indicating the tendency to recognize facial expressions as threatening, was expected to reflect paranoia. Against theoretical expectations, heightened paranoia questionnaire scores were associated with a non-liberal bias, which was not affected by negative emotion per se. However, subsequent analyses revealed that, if anxious, participants with heightened paranoia adopted a comparatively more liberal response bias. These findings corroborate the eminent role of anxiety in paranoia and demonstrate that state paranoia can be captured with the presented paradigm.

The measurement of delusional ideation in the normal population—-introducing the PDI (PEters et al. delusions inventory)

Research increasingly assesses momentary changes in paranoia in order to elucidate causal mechanisms. Observed or manipulated changes in postulated causal factors should result in fluctuations in state paranoid ideation. Previous studies often employed a state-adapted Paranoia Checklist (Freeman et al., 2005) to measure state paranoia. This study examined whether the Paranoia Checklist or subsets of its items are appropriate for this purpose.Thirteen studies (N=860) were subjected to meta-analyses of each Paranoia Checklist item. We selected items based on (1) whether they showed pre-to-post change in the expected direction and (2) whether this effect was larger in experimental vs. control conditions. All resulting item selections were cross-validated on a hold-out sample (n=1893). Finally, we explored how much variation in paranoia was captured by the state-adapted version in a brief ambulatory assessment study (N=32).A thirteen item State Paranoia Checklist as well as a five item and a three item Brief State Paranoia Checklist were extracted. Cross validation revealed better model fit and increased sensitivity to change. Multilevel analysis indicated 25-30% of the variance in the Brief State Paranoia Checklists to be due to intra-individual daily fluctuations in paranoia.Our analyses produced reliable and valid revised scales. Increases in change sensitivity indicate that future assessment of state paranoia in experimental and ambulatory assessment studies can be optimized by using the revised scales.